Images from the ArcticPaul Nicklen's curiousity about animals in the Arctic has led him to lots of close encounters. One of those encounters was with a sharp toothed leopard seal, an animal he says is both aggressive and playful.10:06 a.m.

The list of threatened species growsThe World Wildlife Fund has released it's latest list of the most threatened species on the planet. New additions to the list include the Pacific walrus, bluefin tuna, and the monarch butterfly.10:45 a.m.

Guests

Sybille Klenzendorf: Managing director of the species conservation program at the World Wildlife Fund.